Objective: The aim of this study was to evaluate the severity of illness of children admitted to paediatric intensive care units in the Czech Republic and to evaluate mortality, predicted mortality and their ratio (SMR – Standardized Mortality Ratio). Design: Prospective observational multicentre study between January 1, 2001 and January 1, 2002. Setting: Eleven paediatric intensive care units in the Czech Republic. Material and Methods: All children admitted to the paediatric intensive care units of involved hospitals during 2001 were enrolled. The admission PRISM score was calculated in all children. A predicted mortality was determined and a real mortality and SMR ratio was recorded. Moreover all these parameters were determined for particular categories of patients according to the level of the admission PRISM score (0–4, 5–9, 10–14, 15–19, 20–24, 25–29, ≥ 30). Results: 2934 consecutive patients were enrolled in the study with a mean length of stay of 5.4 days and a mean PRISM score 5.6. Predicted mortality calculated from PRISM score was 4.6 % (135 deaths were predicted). The real mortality was 3.1 %, 92 patients died. The Standardized Mortality Ratio was 0.68. The real mortality was lower than predicted in all groups of patients according to the level of the admission PRISM score (SMR < 1). Conclusion: The mean PRISM score of children admitted to paediatric intensive care units in the followed period was 5.6, which predicted a mortality of 4.6 %. The real mortality was 3.1%and Standardized Mortality Ratio 0.68. These data support the evidence of a very good quality of care in paediatric intensive care units.

        Key words: PRISM score – intensive care – Standardized Mortality Ratio – children – quality of care